Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Wheelchair accidents cause injuries with short and long-term consequences (e.g., bed rest, hospitalization, additional disabilities). The medical and recovery expenses of these accidents impose significant economic and social burdens to the patient and the healthcare system (often between $25,000 and $75,000). Over the last 14 years, such accidents registered a compound annual growth rate of 5% where the total number of wheelchair riders has also grown at the same rate. Despite the high accident rate and high cost of incurring these injuries, there are very few technologies to protect the wheelchair riders in case of a fall.
One of these technologies is using anti tippers, which are offered in most power wheelchairs as an “add on” option. Front and rear anti-tippers are attached to increase stability on inclined terrain. But there are no anti tippers to make the chair stable in side falls. Moreover, the main reason for using anti tippers is preventing fall. In case of a fall accident, anti-tippers would not provide any protection to user's critical body parts.
In addition, since 2007, ten million Americans were diagnosed with osteoporosis and 329,000 hip fractures have since been reported. Femoral neck (found in the hip joint) of elderly people can become fragile due to the age. An impact, such as a fall, creates a torque on the femur shaft and femur head that can break the femur neck. One of the highest risks of hip fracture is the post-fracture consequence, such as infections, cardiovascular events, and thromboembolism. These consequences have been linked with a high death rate. Due to an increase in life expectancy, hip fractures are expected to rise from 1.66 million in 1990 to 6.26 million by 2050.
Using traditional airbags on wheelchairs, which are single use airbags, can be expensive and complicated for average wheelchairs/power chairs. Traditional airbags also use chemical reaction which is difficult to control and can be dangerous.
A wearable airbag system disclosed by Fukaya et. al. “Protection against impact with the ground using wearable airbags”, Ind Health, 2008, 46(1), 59-65, relies on a one time use container of compressed gas to inflate the airbag(s). While compressed gas containers, are safer and more cost efficient than traditional airbags, there are problems associated with them as well. They are one-time use which means that once the compressed gas is expelled, the container must be replaced or re-filled with gas prior to the next use. The size and deployment time of airbag is also limited to the size and pressure of the gas container.
Furthermore, wearable airbag system configurations include a body-worn gear, which is detachably fitted to the wheelchair user and to which the air bag is attached, to ensure that the air bag may cover the determined parts of the user. So, in order to protect the rider, he/she needs to wear an extra piece of clothing which is heavy and bulky. The inconvenience causes less compliance among riders and as a result, the chance of protecting during fall decreases.